In Celestial Mechanics the equation: LP = w + N (Longitude of the Perihelion = Argument of the Perihelion + Longitude of the Ascending Node) is confusing. Both "LP" and "N" are on the Ecliptic Plane but "w" is not. "w" is on the Elliptic Plane with a tilt of "i" Inclination from the Ecliptic Plane at "N". Even though "i" is small then projection of "w" onto the x-y axis of the Ecliptic Plane is different than just plain "w". How do you explain for this discrepancy?